Chrome includes Adobe's flash plugin, and there aren't any gotchas about installing it. The caveat is that it's not a full system-wide installation - This isn't a solution if you want to double-click on .swf files, but is a simple solution if you just want to quickly browse flash-enabled websites.
As an added bonus, the version of flash that is shipped with Chrome is tweaked to work inside of Chrome's PPAPI plugin model, which allows Chrome to actually know and display which tabs have flash actively producing sound. There's also no nagging Adobe updater (Chrome automatically updates the built-in flash module when it updates itself).